29,401 research outputs found
Superdescendants of the D1D5 CFT and their dual 3-charge geometries
We describe how to obtain the gravity duals of semiclassical states in the
D1-D5 CFT that are superdescendants of a class of RR ground states. On the
gravity side, the configurations we construct are regular and asymptotically
reproduce the 3-charge D1-D5-P black hole compactified on . The
geometries depend trivially on the directions but non-trivially on the
remaining 6D space. In the decoupling limit, they reduce to asymptotically
AdS spaces that are dual to CFT states obtained by
acting with (exponentials of) the operators of the superconformal algebra. As
explicit examples, we generalise the solution first constructed in
arXiv:1306.1745 and discuss another class of states that have a more
complicated dual geometry. By using the free orbifold description of the CFT we
calculate the average values for momentum and the angular momenta of these
configurations. Finally we compare the CFT results with those obtained in the
bulk from the asymptotically region.Comment: 50 pages; v2: corrected typos; v3: corrected typos, eq. (2.9b)
simplifie
The decay of massive closed superstrings with maximum angular momentum
We study the decay of a very massive closed superstring (i.e. \alpha' M^2>>
1) in the unique state of maximum angular momentum. This is done in flat
ten-dimensional spacetime and in the regime of weak string coupling, where the
dominant decay channel is into two states of masses M_1, M_2. We find that the
lifetime surprisingly grows with the first power of the mass M: T =c \alpha' M.
We also compute the decay rate for each values of M_1, M_2. We find that, for
large M, the dynamics selects only special channels of decay: modulo processes
which are exponentially suppressed, for every decay into a state of given mass
M_1, the mass M_2 of the other state is uniquely determined.Comment: 22 pages, 4 figure
Multi-loop open string amplitudes and their field theory limit
JHEP is an open-access journal funded by SCOAP3 and licensed under CC BY 4.0This work
was supported by STFC (Grant ST/J000469/1, ‘String theory, gauge theory & duality’)
and by MIUR (Italy) under contracts 2006020509 004 and 2010YJ2NYW 00
Matching the (DR4)-R-6 interaction at two-loops
The coefficient of the interaction in the low energy
expansion of the two-loop four-graviton amplitude in type II superstring theory
is known to be proportional to the integral of the Zhang-Kawazumi (ZK)
invariant over the moduli space of genus-two Riemann surfaces. We demonstrate
that the ZK invariant is an eigenfunction with eigenvalue 5 of the
Laplace-Beltrami operator in the interior of moduli space. Exploiting this
result, we evaluate the integral of the ZK invariant explicitly, finding
agreement with the value of the two-loop interaction predicted
on the basis of S-duality and supersymmetry. A review of the current
understanding of the interactions in type II superstring
theory compactified on a torus with and is
included.Comment: 40 pages, various typos and coefficients corrected in version
Pharmacogenetics of analgesic drugs
• Individual variability in pain perception and differences in the efficacy of analgesic drugs are complex phenomena and are partly genetically predetermined. • Analgesics act in various ways on the peripheral and central pain pathways and are regarded as one of the most valuable but equally dangerous groups of medications. • While pharmacokinetic properties of drugs, metabolism in particular, have been scrutinised by genotype–phenotype correlation studies, the clinical significance of inherited variants in genes governing pharmacodynamics of analgesics remains largely unexplored (apart from the µ-opioid receptor). • Lack of replication of the findings from one study to another makes meaningful personalised analgesic regime still a distant future. • This narrative review will focus on findings related to pharmacogenetics of commonly used analgesic medications and highlight authors’ views on future clinical implications of pharmacogenetics in the context of pharmacological treatment of chronic pain
Probabilistic abductive logic programming using Dirichlet priors
Probabilistic programming is an area of research that aims to develop general inference algorithms for probabilistic models expressed as probabilistic programs whose execution corresponds to inferring the parameters of those models. In this paper, we introduce a probabilistic programming language (PPL) based on abductive logic programming for performing inference in probabilistic models involving categorical distributions with Dirichlet priors. We encode these models as abductive logic programs enriched with probabilistic definitions and queries, and show how to execute and compile them to boolean formulas. Using the latter, we perform generalized inference using one of two proposed Markov Chain Monte Carlo (MCMC) sampling algorithms: an adaptation of uncollapsed Gibbs sampling from related work and a novel collapsed Gibbs sampling (CGS). We show that CGS converges faster than the uncollapsed version on a latent Dirichlet allocation (LDA) task using synthetic data. On similar data, we compare our PPL with LDA-specific algorithms and other PPLs. We find that all methods, except one, perform similarly and that the more expressive the PPL, the slower it is. We illustrate applications of our PPL on real data in two variants of LDA models (Seed and Cluster LDA), and in the repeated insertion model (RIM). In the latter, our PPL yields similar conclusions to inference with EM for Mallows models
Spectrum-line reversal measurements of free electron and coupled N2 vibrational temperature in expansion flows
Spectrum line reversal measurements of free electron and coupled nitrogen vibrational temperatures in expansion flow of shock tub
The impact of the mode of thought in complex decisions: intuitive decisions are better
A number of recent studies have reported that decision quality is enhanced under conditions of inattention or distraction (unconscious thought; Dijksterhuis, 2004; Dijksterhuis and Nordgren, 2006; Dijksterhuis et al., 2006). These reports have generated considerable controversy, for both experimental (problems of replication) and theoretical reasons (interpretation). Here we report the results of four experiments. The first experiment replicates the unconscious thought effect, under conditions that validate and control the subjective criterion of decision quality. The second and third experiments examine the impact of a mode of thought manipulation (without distraction) on decision quality in immediate decisions. Here we find that intuitive or affective manipulations improve decision quality compared to analytic/deliberation manipulations. The fourth experiment combines the two methods (distraction and mode of thought manipulations) and demonstrates enhanced decision quality, in a situation that attempts to preserve ecological validity. The results are interpreted within a framework that is based on two interacting subsystems of decision-making: an affective/intuition based system and an analytic/deliberation system
Security policy refinement using data integration: a position paper.
In spite of the wide adoption of policy-based approaches for security management, and many existing treatments of policy verification and analysis, relatively little attention has been paid to policy refinement: the problem of deriving lower-level, runnable policies from higher-level policies, policy goals, and specifications. In this paper we present our initial ideas on this task, using and adapting concepts from data integration. We take a view of policies as governing the performance of an action on a target by a subject, possibly with certain conditions. Transformation rules are applied to these components of a policy in a structured way, in order to translate the policy into more refined terms; the transformation rules we use are similar to those of global-as-view database schema mappings, or to extensions thereof. We illustrate our ideas with an example. Copyright 2009 ACM
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